Here's my method (basically with post-GC a lot of Choice's tricks that were originally required to beat the fight aren't anymore, so I took the dumb way out):

Phase 1: Don't infest game. Just walk in a circle, let as many Horrors and Ghouls up as possible. Don't consecrate, use HA/AW on CD for DPS. Phase should last about 3:30-ish.

Transition 1: Stay until LK is down to about 68% (1-2 ice spheres) then run to the throne, kill raging spirits (you should be able to kill all 3) before LK quakes and becomes active.

Phase 2: Burn LK, begin using Consecrate at around 50%.

Transition 2: Stay and burn LK down to ~36-37% (1-3 ice spheres), then run to the throne again. Consecrate in your rotation. You should be able to kill 2 raging spirits during this transition, then begin focus on LK. This means you only have 2 spirits up which gives a lot better survival chances in P3. Should be done at about ~9 minutes.

Phase 3: Burn as hard as possible, make sure you are getting your spells (consecrate, how, hw, and especially execution sentence) out when not silenced. When pulled in try to get a sacred shield at the last possible second of your vengeance stack, make sure you get 5 HP from judging before you get out.

First phase never took longer than 4.5minutes for me. Kiting LK on the outer circle and not hitting any adds at all. Could be a gear issue, but I started reliably soloing LK when I reached ilvl 505 I think.
Also, I don't really bother killing Spirits now, just facerolling through their silences. IF you time everything correctly, there's no need to touch them at all.

yeah im getting closer now. below 4min in p1. cheesing by not kiting. just stand on stairs and soak traps for vengance. then kill of 1 or 2 spirits depending on how it loooks during transition. still rng ****blocks me but its getting closer. havent slept in 2 days either so a bit unfocsed

do not care a living shit about the mount either anymore.. i hate him so much now i just want him dead.

Get Tidy Plates, filter away Shambling Horror, Raging Spirit and Drudge Ghoul. Single-Target build, 20/20 DP glyph.
Vengeance is your friend. From my first kill (~506ilv, mainly retribution haste gear with shitty 496 weapon and 489 shield lol, softcap) that was the rule. With high vengeance 700haste elixir > 1000str flask imo. Haste food (yea, the one from vendor in shrine). Haste makes waste.
P1: Stand on the throne, hug the "back" of chair on right side. Traps explode, dmg you, youre not flying. Prepot. Single target LK, no consecration. More adds, more GC, more HoPo, more DPS. You can play with infest at the start, but beware when your AD fades - LoH between tick healing to 15% (AD) and next tick that will kill you. SoI (after you finish playing with infest, if you do), ignore SS. Wings, Avenger, nuke. You should have time to use 2 avengers in P1 - use potion on 2nd avenger. Further you go, rotation is closer to AS,AS,AS, Finisher. SS when running from throne to platform, anyway before first spirit spawn.
T1: Keep wings for that. Keep sacred shield up - crucial. Keep J or AS for Ice Spheres. Strafe around to have LK between you and sphere. Nuke LK. Sphere lands, J or AS it (both can be used when silenced). Dont waste a moment to refresh SS when youre not silenced.
P2: Defile is your friend. With gear ~520 you can ignore spirits tbh, just be aware of infest+defile+silence. Keep SS up, refresh when possible (but dont panic, its not rly needed to refresh it every 8-10secs). All cooldowns are your friends here. Keep in mind bug with ghouls - you can leave it alive but then you have to avoid any dmg inside frostmourne - taking dmg from wicked spirit or shadow bomb will instakill you. If you decide to kill ghouls, 45% is usually best time to start aoe.
T2: Same as T1. AoE rotation to be sure ghouls will die, if you decide to kill them. Wings here if you didn't use them in P2.
P3: Basically same as P2, with frostmourne exception. Still ignore spirits, as you wont have as much vengeance as you had in P2 anymore.
Frostmourne: Refresh SS. Heal yourself up (sometimes from 30-50% hp). Dont take any dmg till last secs of Vengeance (in my case usualy 80-90k when entering frostmourne) or it will refresh it but with low value. Refresh SS on last secs of high vengeance for high absorb (you will have 1-2 ticks of SS when it will tp you out). Get 5 HoPo on spirits in the meanwhile. Use a cooldown (preferably DP) just before TP out.
P3 TP Out: Dont panic, you have active CD for next 10secs and around 8-10secs of SS up. Shield the LK, AoE-Hammer, Shield the LK. Defile. If silenced, move out of defile until SS up, if not, refresh SS and eat defile for vengeance. Avenger, Wings, Nuke. Repeat until 93M dmg done on LK.

weapons are the biggest on dmg output......
i play as tank if i equip dps weapons if goes up ..alot

As a DK - maybe. Paladins have only one ability that relies on your weapon damage, and that is Crusader Strike (which is about 7-10% total damage done). Everything else is reliant purely on your attack power.
edit: HotR is weapon damage too, obviously, but you don't need to use it often there.

weapons are the biggest on dmg output......
i play as tank if i equip dps weapons if goes up ..alot

You play as a dk tank. Big difference. This thread is about prot paladins.

Volun-told - A supposedly optional event, award, assignment, or activity in which a person (or persons) are required to attend either by persons-in-charge nominating them or their peers expecting them to be there. The individual often has no say in the matter, and non-attendance in frowned upon.I am so tired of seeing terrible people, being admired, for being terrible people.

Just for those who are wondering about glyphing Focused Shield.
Tried it without glyph of FS last reset. Ended up with all ghouls dead before 2nd transition and barely made it to 10% 8 seconds after enrage. While this removes the need to spam aoe abilities to get ghouls down, it nerfs boss dps by a large margin (my usual kills happen 3 mins before enrage) and removes tons of GC procs. Not gonna do that again, for sure.

Very(I first started at 510 ilvl ret with a 471 shield), I would suggest though that you make a macro for ice spheres and lk(put judgement in the macro and don't use it on anything but spheres during transitions) because you will need to stay in for transitions to kill him before his enrage.

It occurs when mobs are too close to him, putting him in combat. They return to their spawn points so as long as you stay away from the middle in p1 you shouldn't get it.

If it does happen, it's not the end of the world. After it bugs you can actually release and run back, pick up the mobs close by and hit him to re-engage him. Once the mobs are dead the RP should begin immediately.

It is. Drudge Ghouls in P3 = often fail in frostmourne.
You can always try to get rid of P3 by making P1 way longer (Im picking shitty weapon and dump all HoPo into WoG, basically I'm barely attacking him, just to stay alive). Get more adds, nuke like shit, release spirit in case of not enough dps to bring him down to 10% during T2 (around 480-490k dps = ~31M / ~65secs)

im on a mental breakdown on this crap.. i dont get it. im either dying from RNG or lack of dps.. im pulling my hair out here.. literally.

I really don't understand, you must be doing something wrong with the rotation, I'd find it incredibly hard to die on this fight even if I was trying. Which t45 talent are you running? Eternal flame is better HPS on yourself than sacred shield is, that might help the death issues.

im on a mental breakdown on this crap.. i dont get it. im either dying from RNG or lack of dps.. im pulling my hair out here.. literally.

If it's your armory in your sig - you're missing focused shield / focused wrath ghyph. You'll run out of trash before end of T1 this way. You wont get dps then.
More GC procs = more HoPo, bigger uptime on SoTR, less dmg taken.
You can always try to post some logs of your attempts. Hard to say where you do something wrong.

Honestly I have no idea why ppl bless EF so hard. I believe it's doable even without any L45 talent. Healing from SoI goes way into overheal anyway. Maybe matter of habits or dunno, I always prefered SS over EF and had no bigger problems with killing it with SS.